How mathematics can help to solve the current water crisis

Population growth, drought and contamination mean that water quality and quantity concerns are one of the largest environmental issues facing the world today. As a result, the race to find new and effective strategies for the production of clean water is now more important than ever.

Here in Oxford we have been working with Pall Corporation for the last 30 years, one of the world’s leading filtration and separation science companies. During this time we have derived a suite of mathematical models for a variety of filtration strategies [M.P. Dalwadi et al. 2015, Proc. Roy. Soc. A; I.M. Griffiths et al. 2014, J. Coll. Interf. Sci.]. Our mathematical theories allow us to understand the inner workings of a filter during operation (which is impossible to know from experiments without dismantling the filter), allowing us to optimize current techniques and identify new filtration strategies that maximize output for minimum energy usage.

Since 2011 our partnership with Pall Corporation has developed significantly and we now have a dedicated collaborative team, headed by Dr Ian Griffiths, Dr Maria Bruna and Professor Colin Please. One of the key challenges we faced was in the technology translation. While our theories were able to describe the experimental observations and offer key insight, those technological discoveries were not readily translated back into industry. To overcome this hurdle we developed the online interface MEMFI (www.memfi.co.uk), which enables users within industry to interact with our models dynamically, tweaking dials to match a given filtration scenario and instantly seeing the predicted outputs on their screen. The interface also serves to engage researchers in our field by offering a more immersive experience than an academic paper alone. The website includes a short description of the problem and the model assumptions. The ultimate aim is to centrally host all of the models that we develop in our group to offer a comprehensive filtration repository.

Schematic of possible blocking mechanisms in dead-end filtration [I.M. Griffiths et al. 2014 J. Coll. Interf. Sci.]

Schematic of mechanisms for particle transport in a cross-flow filter [J.G. Herterich et al. 2015 Phys. Fluids].

To find out more, or get involved, check out www.memfi.co.uk and Water Purification in Oxford, or contact Ian Griffiths (ian.griffiths@maths.ox.ac.uk).